A lot of the teams in front of ISU in the CFP rankings would need to lose twice for ISU to jump over them.
In the SEC, Bama and Ga are undefeated. The loser of the SEC CCG would still get in the CFP over a 2-loss ISU.
In the Big Ten, if OSU or Wisc win the CCG, the loser of the CCG is probably out, but it would be tempting to take an 11-1 PSU over a 2-loss ISU.
Interestingly, ISU needs to root hard for Iowa to win out. Not only does that help ISU's SOS, but that would give OSU and Wisc each an unexpected loss. Still, its hard to imagine a scenerio will the Big Ten gets left out entirely.
The ACC or Notre Dame will probably get a team in. Either Miami or Notre Dame, but not both, or maybe Clemson.
The PAC is close to being left out again. Their only hope is a 1-loss Washigton wins out.
So in summary, I could see final rankings like this
1. Undefeated Bama/Ga winner
2. Big Ten CCG game (OSU/Wisc) winner
3. 1-loss Bama/Ga loser
4. 1-loss ND
5. 1-loss Clemson/Miami winner
6. 1-loss PSU
7. 2 loss Big 12 champ ISU
8. 2 loss PAC ccg winner (Wash?)
9. 2-loss Miami/Clemson loser
10. Big Ten CCG (OSU/Wisc) loser